Welcome to HVAC-Talk.com, a non-DIY site and the ultimate Source for HVAC Information & Knowledge Sharing for the industry professional! Here you can join over 150,000 HVAC Professionals & enthusiasts from around the world discussing all things related to HVAC/R. You are currently viewing as a NON-REGISTERED guest which gives you limited access to view discussions

To gain full access to our forums you must register; for a free account. As a registered Guest you will be able to:

Participate in over 40 different forums and search/browse from nearly 3 million posts.

in florida there is little to no metal. industrial would be the exception. residential you see flex,maybe on custom homes you might see it all hardbord but that's if it's requested and i do a few but 99% is flex. commercial is duct board and some flex. i hear a lot of stories on here from people talking about only doing metal i guess that's up north never seen much here. sounds like the contractors up there spend alot more time on the jobs to complete than we are given here also. it's a bidding war here and the lowest bid usually wins so you have to find the medium between quality work and speed if you like you're job. in a perfect world it would be quality first!

Been using ductboard for over 20 years. We first used Knauf brand then we switched to Owens Corning Enduracoat. A couple of years ago they dropped it and now they just have Endurogold. It is not nearly as good. I think the Manville product looks good. Owens-Corning has a terrible customer service. You can never find any of their people to talk to. If they would put the EndroCoat back on the market I think they would have alot of buyers. We put ductboard in all the new houses we do. We use sheet metal in the change outs{with existing metal work}. I sometimes get hassles from people about using it but,I haven't found any trouble with it.It is quiet and has good thermal properties. I hand cut all mine on the job so I have very little waste. Bottom line is I like it.

The 800 board is in fact more dense. Most commonly used in commercial applications it can be cut with hand tools or with a machine. I prefer to use my "red" and "blue" hand tools, the "red" has a "V" cut which i feel gives a tighter fit when stapled. Trying to convince my Boss to start using the 800 board for all applications cause it holds up better, lasts longer and has a higher "R" value. Sorry so long winded, hope I answered your question.

we use metal here, w/flex, for attics. middle of Missouri (Gem of the Louisiana purchase, BTW, according to either Lewis or Clark, can't remember which. too cold in winter too hot in summer, I say)

I have been told the inside of flex install will let some loose fibers go for a while. Is this true?

We have one customer, an old timer who does a few custom houses still and he specs duct board cause he says its quiet. I haven't been on any of those jobs but it looks like a hoot to get to use those tools. Bet it's blow and go. Warn the spark-tricians, plumbers and the insulators not to stomp too hard on it, I guess!

Originally posted by centralflinstaller i hear a lot of stories on here from people talking about only doing metal i guess that's up north never seen much here. sounds like the contractors up there spend alot more time on the jobs to complete than we are given here also.

I guarantee that you are mistaken about the time it takes to install sheet metal ductwork.

LOL, good post Bat. If you're refering to flex duct losing fibers, I have'nt seen or heard of that happening. The newer ductboard had a coating on it to prevent fibers from turning loose while the system is running. As far as people stepping on or crushing ductboard, that will always be a problem, but I can promise you that after they get a couple bills from us because we had to replace crushed trunkline, they usually walk a little softer. Metal and ductboard both has pros and cons, I have a metal plenum on my system, and even though its cross broke and installed properly I can still hear it flex and "pop" when my furnace kicks on. But then again this is just a rental house so I aint gonna fix it.

Right you are duct dr...when those rodents get hungry or their teeth need trimming they will eat almost anything. My buddy who just moved to Florida (and he turned his house upside down looking for his duct board tools, guess what he's going to be doing) was telling me about a couple jobs where they fixed duct board the mice ate into. Gobbled flex, this I can easily believe. Saw a furnace last fall where the little rats got in and gnawed insulation off a bunch of wires. Makes you want a cat around, I guess. We have pulled little mouse babies out of condensate drains and a guy was telling me about finding one in an inducer fan, which absolutely strains credulity.